Multiple Switch statements in a single iRule

Yes, but what you really want to do is use a Data Group. Let's say you have a Data Group that looks like this:

create ltm data-group internal dg-address-matchers type ip \
  records add { 10.11.0.0/16 { data "action1" } \
                10.12.0.0/16 { data "action2" } \
                10.13.13.0/22 { data "action3" } ... }

You would then use it thusly:

when CLIENT_ACCEPTED {
    set indicator [class lookup [IP::client_addr] dg-address-matchers]
        
    switch [class lookup [IP::client_addr] dg-address-matchers] {
        action1 {
             ... do something ...
        }
                
        action2 {
             ... do something else ...
        }
        
         ... etc ... 
        
        "" {
             this means the IP matches no netblocks in the data-group
        }
    }
}